June 20, 2012|BY WILLIAM WEIR, bweir@courant.com, The Hartford Courant

The American Medical Association Wednesday adopted recommendations based on a report co-authored by a University of Connecticut researcher asserting that certain types of nighttime lighting can adversely affect health and may be linked to breast cancer and other medical conditions.

The AMA's house of delegates voted to adopt policies based on the report "Light Pollution: Adverse Health Effects of Nighttime Lighting," co-authored by Richard Stevens, an epidemiologist at the University of Connecticut Health Center. He was one of four writers.

With the AMA accepting the report, Stevens said, funding should become more readily available for further research.

"There is no question that lighting suppresses circadian rhythms," he said, adding that the next step will be to determine how much it affects specific medical conditions.

Dr. Steven Lockley, a professor of medicine at Harvard University and one of the report's four authors, said the AMA's policies will help educate the public about artificial light, particularly regarding the risks of working night shifts. Studies consistently have shown that shift workers are at a higher risk for breast cancer, heart disease and other health problems.

"The main goal is to increase the awareness of the general health risks, so that people can make informed decisions about their health," he said.

With Wednesday's vote, the AMA now recommends that new technologies be developed to reduce the health risks of indoor and outdoor lighting and calls for more research into the health risks and benefits of exposure to nighttime lighting in workplaces.

The AMA also recommends that any workplaces with night-shift employees should establish an "employee fatigue risk management plan."

Another of the report's co-authors, Dr. David Blask of the Tulane University School of Medicine, said the AMA's action should bring the issue more into the mainstream.

"A major effect of this is that it's going to put those in the scientific community who are on the fence or wary of this area on notice that it's time to get on baord with this, that this is the real deal," Blask said. "And that it has the potential to affect all of us, in addition to shift workers."

"I think it's a big deal," Stevens agreed. "This is a turning point event. When I got started on this, it was like a blip on the radar screen."

Stevens has been studying the effects of nighttime lighting for 25 years and was the first researcher to raise the possibility that there might be a connection to breast cancer.

"I asked in a published a paper in 1987: Could the increase in electric light explain the pandemic of breast cancer?" he said. Stevens co-authored nine of the 134 studies cited in the report.

Like a lot of new scientific concepts, he said, the theory seemed on the fringe at first. But it has slowly gained traction, and more researchers since have focused on other possible adverse health effects of artificial lighting, such as obesity and mood and sleep disorders.

"It's an exploding area, and it's very exciting," he said.

Stevens' theory is that exposure to artificial light for prolonged periods will disrupt the body's biological clock that regulates sleep and wakefulness, known as circadian rhythms. Electric light — around for only the past 150 years — has impaired these natural rhythms, which have evolved over millions of years. As a result, Stevens said, hormone and melatonin levels are disrupted and that could lead to the onset of breast cancer.

The report calls artificial light "a man-made self-experiment" that throws sleep out of whack. It also asserts that excessive light at night — including light from TVs and computers — can cause sleep disorders, especially in children and adolescents.